Above. Figure 8 from Breuil et al. (2020) showing the dorsal carpet pattern of young adults Iguana melanoderma. A Montserrat B Saba. The dorsal coloration is formed by darker more or less interrupted dorso-ventral bands (brown, dark grey) on a lighter ground. This pattern disappears in old individuals. The black patch between the eye and the tympanum is already visible.
The Lesser Antilles is inhabited by three species of the genus Iguana the Lesser Antillean Iguana, Iguana delicatissima, which is endemic to the northernmost islands of the Lesser Antilles, the introduced common Green Iguana from South America, Iguana iguana iguana, that is represented also by the two newly described endemic subspecies Iguana iguana sanctaluciae from Saint Lucia and Iguana iguana insularis from Saint Vincent and the Grenadines, and Grenada, and the introduced Iguana rhinolopha from Central America.
Using morphological and genetic data, Breuil et al. (2020) described the Iguana populations from the islands of Saba and Montserrat as a new species, Iguana melanoderma. This species is recognized on the basis of the following combination of characteristics: private microsatellite alleles, unique mitochondrial ND4 haplotypes, a distinctive black spot between the eye and tympanum, a dorsal carpet pattern on juveniles and young adults, a darkening of body coloration with aging (except for the anterior part of the snout), a black dewlap, pink on the jowl, the high number of large tubercular nape scales, fewer than ten medium-sized triangular dewlap spikes, high dorsal spikes, and lack of horns on the snout. This new melanistic taxon is threatened by unsustainable harvesting (including for the pet trade) and both competition and hybridization from escaped or released invasive alien iguanas (I. iguana iguana and I. rhinolopha) from South and Central America, respectively. The authors call for action to conserve Iguana melanoderma in Saba and Montserrat and for further research to investigate its relationship to other melanistic iguanas from the Virgin Islands and coastal islands of Venezuela.
Citation
Breuil M, Schikorski D, Vuillaume B, Krauss U, Morton MN, Corry E, Bech N, Jelić M, Grandjean F (2020) Painted black: Iguana melanoderma (Reptilia, Squamata, Iguanidae) a new melanistic endemic species from Saba and Montserrat islands (Lesser Antilles). ZooKeys 926: 95–131. https://doi.org/10.3897/zookeys.926.48679
